Food allergy

Food allergy is an immune response to food that can be classified as immunoglobulin (Ig)-E and non-IgE mediated. Milk, egg, peanut, tree nuts, and fish are among the most prevalent causes of food allergy. Mild reactions can include itchy rash, watering eyes, and nasal congestion while a severe reaction results in anaphylaxis. A detailed clinical history is essential when making a diagnosis, and skin prick testing and quantitative measurement of food-specific IgE antibodies can be helpful. Cow milk protein allergy causes a plethora of symptoms and frequently resolves spontaneously over the first 2 years of life; diagnosis is based mainly on clinical history. Food challenges have a pivotal role in the diagnosis of food allergy. Introduction of ‘allergic’ foods at 3–6 months alongside continuing breastfeeding may prevent allergy.